White Papers & Technical Articles

Authors: Haider Razak, Manish Saraf

This paper provides an in-depth analysis of the issues and challenges of motor drive systems in industrial application with long cable lead. Moreover, it presents a simple and economical filtering solution to these challenges under different system parameters and operating conditions. The system parameters include cable length, cable size, cable type, and drive system size. The operating conditions include switching frequency, output operating frequency, and loading condition. The motor peak voltage, which is the main concern in such applications, is investigated along with the power dissipation of the filter.

Authors: Haider Razak, Manish Saraf, Paul Baker, Sanela Ligata

This paper provides in-depth analysis of the issues and challenges of motor drive systems in industrial application with long cable lead. Moreover, it presents an innovative sine wave filter solution to mitigate the motor peak dvdt voltage and its harmonics. The proposed filter utilizes the core material to provide damping to the resonance issue of a typical sine wave filter. The motor peak voltage, common mode current and voltage total harmonics distortion (THD) are investigated under different system parameters and operating conditions, which include switching frequency, motor operating speed, and motor loading condition. Three motor drive systems (10HP, 25HP and 100HP) with different cable lengths (150m- 1000m), and cable sizes (#8, #2, 4/OT) are used to experimentally validate the design and analysis of this paper.

Authors: Dr.-Ing. Peter Wallmeier, Dr.-Ing. Haider Razak, Carlos Martinez de Guereñu, Andre Kotthoff

AI rack power has climbed from tens of kilowatts to several hundred within two GPU generations, with roadmaps converging on one-megawatt racks before the decade ends. The conventional train fails on loss, copper, footprint, component count, and storage integration. The answer is a single conversion from medium-voltage AC to a facility-level 800VDC backbone. This paper argues that the line-frequency transformer (LFT) plus solid-state rectifier (Transformer Rectifier Unit or TRU) is the right way to build it now. A TRU is estimated to deliver ≈98.5% MV-to-800VDC efficiency — matching today's solid-state transformer (SST) demonstrators — with a 1:50–100 component-count advantage, MTBF above 250,000 hours, 40–50 year transformer life, better than 3:1 CAPEX advantage, and decades of gigawatt-class field history in both passive multi-pulse (AEG PS’s DC3) and active front-end (AEG PS’s DC4) form. SSTs remain promising but unproven at production scale. AI factories can be energized sooner with TRU while remaining future proof.

Author: Chinmay Shah

A transformer enclosure is the cabinet or housing that covers the core and coil, serving to protect the transformer from environmental factors and safeguard personnel from the transformer itself. Enclosures are a crucial component in ensuring protection against various conditions. Our 3RE Plus enclosure plays a significant role in shielding the transformer from harsh weather conditions.

The purpose of this document is to assist buyers in making informed decisions when choosing transformer enclosures for outdoor applications. This white paper covers industry standards related to outdoor enclosure ratings, common challenges in outdoor applications, and safeguards designed to enhance the transformer's protection against harsh conditions.